Shock absorber for straight bar knitting machine



Aug. 28, 1962 P. G. MCCARTHY 3,050,959

SHOCK ABSORBER FOR STRAIGHT BAR KNITTING MACHINE Filed Sept. 16, 1958 '7 Sheets-Sheet 1 Attorney Aug. 28, 1962 SHOCK ABSORBER Filed Sept. 16, 1958 P. G. MCCARTHY 3,050,969

FOR STRAIGHT BAR KNITTING MACHINE '7 Sheets-Sheet 2 Inventor /m%%,m j la/.

Attorney Aug. 28, 1962 P. G. M CARTHY 3,050,969

SHOCK ABSORBER FOR STRAIGHT BAR KNITTING MACHINE Filed Sept. 16, 1958 7 Sheets-Sheet 3 A ttorn e y Aug. 28, 1962 P. e. M CARTHY 3,050,969

SHOCK ABSORBER FOR STRAIGHT BAR KNITTING MACHINE Filed Sept. 16, 1958 7 Sheets-Sheet 4 lnvento paw-M W I Attorney SHOCK ABSORBER FOR STRAIGHT BAR KNITTING MACHINE Filed Sept. 16, 1958 7 Sheets-Sheet 5 F/GG.

Attorney 1962 P. G. MCCARTHY 3,050,969

SHOCK ABSORBER FOR STRAIGHT BAR KNITTING MACHINE Filed Sept. 16, 1958 '7 Sheets-Sheet 6 Aug. 28, 1962 P. G. M CARTHY SHOCK ABSORBER FOR STRAIGHT BAR KNITTING MACHINE Filed Sept. 16, 1958 7 Sheets-Sheet 7 I nited Patented Aug. 28, 1962 tile 3,050,969 SHUCK ABSORBER FOR STRAIGHT BAR KNITTENG MACHINE Patrick Gideon McCarthy, Loughborough, Leicestershire, England, assignor to William Cotton Limited Filed Sept. 16, 1958, Ser. No. 751,395 Claims priority, application Great Britain Sept. 25, N57 7 Claims. (Cl. 66-43%) This invention is for improvements in or relating to straight bar knitting machines of the type in which a thread carrier bar is reciprocated to the limits of adjustable thread carrier stops by a friction box which is reciprocated, between adjustable stop boxes mounting the carrier stops, by a friction bar.

In an endeavour to minimize the shock of the carrier stops stopping the traverse of the thread carrier bar and consequently stopping the friction box relatively to the friction bar which continues in its travel, it has been proposed to provide buffer means acting on the friction box at the ends of its travel.

The invention provides a straight bar knitting machine of the type referred to having buffer means for the friction box, comprising a slow speed member travelling in the direction of the friction bar, motion transmitting means co-operating between the slow speed member and the friction box and operable by terminating movement of the friction box towards the carrier stops to cause the slow speed member to resist the travel of the friction box to the point of reducing the latters rate of travel to the slow speed of the slow speed member, and resetting means operable to relax the resistance. Conveniently the motion transmitting means includes cam means operative by said terminating movement of the friction box to cause application of the resistance in a predetermined manner governed by the shape of the cam. Conveniently also the motion transmitting means includes a clutch device which is engaged by said terminating movements of the friction box to grip the slow speed member and is disengaged by the re-setting means. Conveniently the cam is shaped to first engage the clutch and thereafter to cam the friction box down to the speed of the slow speed member. The clutch device may be of friction ramp and roller or ball construction. Conveniently the clutch device is adapted for releasable gripping of a slide member to the slow speed member and the cam is mounted on a carrier stop box and is displaceable by said terminating movement of the friction box to engage the clutch by sliding the slide member on the slide. The cam conveniently has a cam surface engageable with a part of said slide to first effect the displacement of the slide and engagement of the clutch and then effect the camming down of the friction box, and a projection on the other side of its pivot in the path of the friction box for operation of the cam thereby.

There may be a limit stop mounted on the stop box for setting the cam in relation to the clutch device, and adjustment means for adjustment of the stop to adjust the relation between the cam and the slide, primarily to adjust the extent of initial movement of the cam required to entirely engage the clutch.

The re-setting means is conveniently pattern controlled from the machines half speed shaft. Conveniently also the slide member provides a tapered space between it and the slow speed member, a clutch roller or ball of the friction roller or clutch device is housed in said space and wedged in the narrow part by the displacement of the slide member, and the re-setting means comprises a lever device operable by a pattern controlled member to displace the roller or ball into the Wide part.

The pattern controlled member is conveniently a bar extending in the direction of the slow speed member for Cir operation of the resetting means at any required position of travel of the friction box.

The invention also provides in a straight bar knitting machine of the type referred to, buffer means for the friction box comprising a slow speed slide bar parallel to the friction bar, a pair of slides on the slide bar adjacent the adjustable carrier stop boxes respectively, a pair of normally broken friction connections one between each slide and the slide bar, a pair of operating members one on each adjustable carrier stop box adapted to be operated by the respective terminating movements of the friction box to displace the respective slides on the slide bar, and consequently make the friction connections to grip the slides to the slide bar and progressively stop the motion of the friction box at each end of its travel, and pattern controlled means to release the friction connections preparatory to the reversing travel of the friction boxes following the travel in each direction.

The above and other features of the invention set out in the appended claims are incorporated in the constructions which will now be described, as a specific embodiment with reference to the drawings accompanying the specification in which:

FIGURE 1 is a cross sectional view of the relevant parts of a straight bar knitting machine employing friction box buffer means according to the invention,

FIGURE 2 is an enlarged plan view of said mechanism,

FIGURE 3 is a further enlarged detail front view part of said mechanism,

FIGURE 4 is a plan view of the mechanism of FIG- URE 3,

FIGURE 5 is a diagrammatic illustration clarifying the action of part of said mechanism,

FIGURE 6 is a plan view of draw'cam-operated friction bar and associated mechanism,

FIGURE 7 is a similar view to FIGURE 5 showing a modification,

FIGURE 8 is an enlarged perspective view of part of the mechanism shown in FIGURE 4, and

FIGURE 9 is an elevational view of FIGURE 8 with parts shown in section.

Referring now to FIGURE 1 the straight bar knitting machine is of the convention type employing beard needles N, sinkers S, thread carriers TC, slurcocks SL, and a friction bar 1 by which thread carriers bars 2 are driven frictionally.

For the purposes of driving the carrier bars 2 frictionally, from the friction bar 1, there is a friction box 3 on the friction bar 1 and a releasable finger connection 4 from the friction box 3 to the appropriate carrier bar 2 (see also FIGURE 2).

FIGURE 2 also shows that the carrier bars 2 have stop lugs 2a which are adapted to engage stop bolts, 5, 5 to limits the carriers movement to that required.

The stop bolts 5, 5 are carried by stop boxes 6, 6 which are mounted on lead screws 7, 7 enabling the stop bolts 5, 5 and consequently the traverse of the thread carriers, to be independently adjustable.

In addition there is provided buffer means for control of the friction box 3 at each end of its travel.

The buffer means consists of a slowly reciprocating bar 8 on which there are slidably mounted slides 9, 9 adapted to be caused by the friction box 3 to have releasable braking connection with the bar 8.

More specifically and with reference to FIGURES 3, 4, 8 and 9, the slide 9, 9' is in the form of a box slidably mounted on the bar 8 and containing a releasable friction device. This device consists of a floating roller 10, 18- mounted in a recess in the box 9, f so as to cooperate at one side with the bar 8 and at the other side with a ramp part 11, 1 1 of the recess. A spring 12, 12 biasses the roller 10, 10 towards that end of the ramp part 11, 11 which is nearest to the bar 8; in other words the ramp 11, 11 forms, with the bar 8, a wedge shaped gap, and the spring 12, 12 urges the roller 10, 10 in a direction towards the narrow end of the wedge shaped gap.

Said floating roller 10, :10 is controlled to obtain a releasable wedge connection between the slide, 9 9 and the bar 8 by movement of the slide 9, 9 relatively to the bar 8 (to make the connection) and by operation of a cam arm 14, 13 on the roller 10, ltl (to break the connection).

More specifically the slide 9, 9 which is biassed by a spring 14, 14 towards the centre of the knitting section, has a roller '15, 15 on it bearing (because of the spring 14, 14 against a cam face 1612, 1th of an operating cam arm 16, 16 which is pivota-lly mounted at 17, 17 on the stop box 6, 6

This operating cam arm 16, 16 is normally urged (by the action of spring 14, 14 on the slide 9, 9 into engagement with an adjusting screw stop 18, 18 (also mounted on the stop box 6, 6 and has a tail Ma, 1611 normally disposed in the path of the friction box.

In operation of this arrangement and assuming, with reference to FIGURE 4, that the friction box 3 is travelling towards the left, the friction box 3 eventually reaches the position indicated in chain dotted lines whereat it engages the tail 16a of the operating cam arm 16; this is a short time before the carrier bar lug 2a (FIGURE 2) reaches the stop bolts 5.

Continued movement of the friction box 3 to the left into the broken line position swings the cam operating arm 16 about its pivot 1'7 so that the cam edge 16b thereon rides against the roller 15 of the slide h and displaces the slide 9 along the bar 8 (which bar is travelling at its slow rate in the same direction as the friction box i.e.

towards the left).

In this operation the slide 9 is displaced at a greater speed than that of the bar 8, and, bearing in mind that in the starting position the roller 1b is maintained by the spring 12 in contact with the opposite faces of the ramp part 11 and of the bar 8, the result is that the roller 10 becomes more tightly wedged between said faces 11 and 10 consequently couples the slide 9 to the bar 8, the travel of the friction box 3 becoming reduced to the slow speed of the bar 8. By the time this happens the carrier bar stop lug 2a has reached stop bolts which positively prevents further travel of both the carrier bar 2 and the friction box 3.

A more detailed effect of the cam operating arm C16 is illustrated in FIGURE 5 from which it will be seen that the cam edge 16b is slightly of S formation whereby constant value movements (indicated by equidistant lines E.L.) imparted by it to the roller 15, and consequently to the slide 9, produces reduction in speed of the friction box 3 in progressively decreasing value movements (indicated by the variable spaced lines VL).

Thus the final movement of the friction box 3 has been buffered as determinedby the shape of the cam face 16b of the cam operating arm 16 acting through the slide 9.

In the modification FIGURE 7 the cam arm 16, has a rounded lead-in portion 16c and the adjusting screw 18 is set such that the rounded portion 16c, causes suflicient movement of the slide in a short initial movement of the cam arm 16 to entirely effect the engagement of the clutch, the friction box thereafter being cammed down in its movement by the remaining cam surface 16b of the cam arm 16. The adjusting screw 18 is adjustable to adjust the extent of movement required of the cam arm 16- to entirely engage the clutch.

When the slide 9 has been reduced to the speed of the bar 8 the latter continues its travel with the friction bar 1 and in so doing acts on the roller to release the connection between it and slide 9.

When the friction bars 1 and 8 have or almost reached the limit of their travel to the left, the cam arm 13 A is swung slightly upwardly to hold the roller 1t? positively out of gripping contact with the ramp part 11 and the bar 8 so that when the friction bar 1 then returns to the right, the bar 8 is similarly allowed to return relatively to the slide 9.

When the friction bar 1 has returned sufiiciently to carry the friction box 3 back from the broken line position to the chain dotted position, the slide also returns to the right to its initial position by the spring 14.

The right hand sides of FIGURES 3 and 4 show that the right hand side mechanism operates in like manner to that described, when the friction box 3 is travelling to the right.

When the friction box has completed its next travel to the right the cam arm 13 is allowed to return in a down- Ward swing to its initial position ready for the next travel to the left.

Conveniently the slow speed bar 8 is driven at speed of the friction bar 1, and for this purpose is driven from the draw mechanism associated with the drive of the friction bar 1.

More specifically, and with reference to FIGURE 6, the friction bar 1 is driven from the main cam shaft 19 at high speed through the bevel gears and cam followers 21, 22 to drive rack 23 which mounts the cam followers 21, 22 and drives a pinion 24: fixed on a spindle 29 to drive the latter, and also to drive a gear wheel 25, also fixed on spindle 29, and driving a rack 2s on the time bar 27, which latter is connected by a bracket 28 to the friction bar 1 and carries the slurcock SL.

The slow speed bar 8 is driven from the draw cam 20 having also on the spindle 29 a smaller pinion 34) which is driven by spindle 29 and meshes with a short rack 31 on the bar 8 to drive the latter. It will be understood that by virtue of the pinon 24 being small and gear 25 large, the bar 8 is driven at low speed and conveniently at A: the speed of the friction bar 1. It will also be understood that the two bars reciprocate in the same directions.

For the purpose of moving the aforesaid cam arm 13, 13 up and down at the required times, the arm 13, 13 has connected to it (see FIGURES 2, 8 and 9) on its pivot 32, 32 a roller arm 33, 33 the roller of this roller arm 33, 33 rests on a bar 34, 34 and this bar 34, 34 is carried on arms by a spindle 35, 35 which is adapted to be rocked when required to operate the roller arms 33, 33 (and consequently the cam arm 13, 13 from a half speed pattern control shaft means 36 through the intermediary of a cam disc 37, 37 a follower lever 38, 38 and interconnecting link mechanism 39, 39

The half speed control shaft 36 is driven from chain and sprocket means 40 (FIGURE 6) and gearing 41 from the main cam shaft 19.

' To operate cam arm 13, 13 to release the roller 10 from its wedge position, the cam disc 37, 37 (FIGURES 2, 8 and 9) is turned at an appropriate time by a rack, in conventional manner, of the half speed shaft 36 so that cam follower lever 38, 38 is operated to displace link mechanism 39, 39 which in turn rocks spindle 35, 35 the latter displacing the bars 34, 34 through interconnecting arms, which in turn operate the roller arms 33, 33 The latter lifts and turns pivot 32, 32 and consequently lifts cam arm 13, 13 the cam surface 13a of which engages the roller 10 and displaces it out of the wedged position.

In the production of fashioned fabric the carrier stop bolts, 5, 5 (FIGURE 2) are adjusted by adjustment of the stop box 6, 6 on the lead screws '7, 7 to vary the traverse of the carriers and friction box.

The stop box 6, 6 carries with it the operating cam arm 16, 16 and the stop 18, 18 (thereby also carrying the slide 9, 9 and associated mechanism with it) so that friction box 3 is buffered at the ends of its movement for any position of adjustment of the stop bolts 5, 5

During said adjustment the roller arm 33, 33 rides along the bar 34, 34 for operating of the cam arm 13, 13 at any position of adjustment of the stop bolts 5, 5

What we claim is:

1. In a straight bar knitting machine, the combination with a reciprocatory friction bar, a friction box on the friction bar and a pair of independently adjustable stops for independently adjusting the end stopping positions of the friction bar, of buffer means for decelerating the friction box comprising a slide bar which is reciprocable at less speed than that of the friction bar, a pair of brake means operably associated with the slide bar for releasable engagement therewith and operable by and on the friction box as it approaches its end positions of stopping by said stops, control means operably associated with the brake means for release control thereof, and means operably associating the brake means and the control means with said stops for like independent adjustments thereof so that operations of the brake means to decelerate the friction box to the speed of the slide bar and release of the brake means can take place for any of the instances of independent adjustment of said stops.

2. In a straight bar knitting machine, the combination with a reciprocatory friction bar, a friction box on the friction bar and a pair of independently adjustable stops for independently adjusting the end stopping positions of the friction box, of buffer means for decelerating the friction box comprising a slide bar which is reciprocable parallel to and at less speed than that of the friction bar, a pair of clutch devices spaced on the slide bar for releasable coupling engagement therewith each clutch device including a slide on said rod displaceable thereon to a coupling position, and a cam for operating said slide and operable by the friction box so that the deceleration is controlled by the shape of the cam as the friction box approaches its end positions of stopping by said stops respectively, a pair of control elements operably associated with the clutch devices respectively for release control thereof, control mechanism operably associated with said control elements for operating them, and connecting means connecting said clutch devices and their respective control elements to said stops respectively for like independent adjustments thereof so that operation of the clutch devices to decelerate the friction box and of said control elements for release control of the clutch devices can take place for any of the instances of independent adjustment of said stops.

3. The combination as claimed in claim 2 wherein each said slide incorporates a ramp forming a wedge recess with the slide bar and a rotatable clutch element operably associated with the wedge recess to be engaged therewith and lock the slide to the slide bar consequent upon the sliding movement of the slide on the slide bar by the friction box, and said control elements are operably associated one with each rotatable clutch element for release of the lock.

4. In a straight bar knitting machine, the combination with a reciprocatory friction box and a pair of independently adjustable stops for independently adjusting the end stopping positions of the friction box, of buffer means for decelerating the friction box comprising a slide bar which is reciprocatable at less speed than that of the friction bar, a pair of brake-applying devices comprising a pair of slides spaced on the slide bar for releasable braking engagement therewith and a pair of cams pivoted to said stops respectively, a pair of adjustable abutment screws for the cams one on each stop, a pair of cam followers one on each slide, a pair of springs each connecting a slide to a stop and thereby biassing the cam followers against their respective cams and the cams against their respective abutment screws, and said cams being disposed to be operable by the friction box as it approaches its end positions of stopping by said stops respectively for the cams to 6 slide the slides into braking engagement with the slide bar and thereby decelerate the friction box in a manner predetermined by the cams, and control means including a pair of control elements operably associated with the slides respectively for release control thereof.

5. The combination as claimed in claim 4 wherein each cam has a substantially S-shaped cam surface operable on its associated cam follower.

6. In a straight bar knitting machine, the combination with a reciprocatory friction bar, a friction box on the friction bar and a pair of independently adjustable stops for independently adjusting the end stopping positions of the friction box, a buffer means for decelerating the friction box comprising a slide bar reciprocatable parallel to the friction bar at less speed, a pair of slide boxes on said slide bar, a pair of roller-and-ramp clutches one in each slide box for releasable clutching of the slides to the slide bar by sliding the slide boxes thereon, a pair of cams pivoted one to each of said stops for operating the slides, a pair of adjustable abutment screws one on each stop for the respective cams, a pair of cam followers one on each slide, a pair of springs each connecting a slide to a stop and thereby biassing the cam followers against the cams and the cams against the abutment screws, said cams having portions in the path of the friction box to be operated thereby as it approaches its end positions of stopping by said stops to decelerate the friction box as determined by said cams, a pair of control levers having rollers, one mounted on each slide and associated one with each clutch roller for release operation of the clutches, and pattern control means for operating the control levers including a pair of rails parallel to the slide bar on which the control lever runners ride respectively to maintain the clutches released for desired periods.

7. In a straight bar knitting machine the combination with draw mechanism, a reciprocatory friction bar, a friction box on the friction bar and a pair of independently adjustable stops for independently adjusting the end stopping positions of the friction box, of buffer means for decelerating the friction box comprising a slide bar, speed reduction means connecting the slide bar to the draw mechanism, a pair of slide boxes on the slide bar adjacent said stops respectively, a roller-and-ramp clutch in each slide box for clutching the slide boxes to the slide bar, a pair of cams pivoted one to each of said stops, a pair of screw abutments on the respective stops for said cams, a pair of cam followers one on each slide, a pair of springs connecting the slides to the respective stops and biassing the cam followers against the cams and the cams against the screw abutments, tail parts on the cams in the path of the friction box for operation of the cams during approach of the friction box to its end positions of stopping by said stops to clutch the slides to the slide bar and thereby decelerate the friction box, a pair of control levers with runners one on each slide and associated with the clutch rollers respectively, and pattern control means for operating the control levers including a pair of rails parallel to the slide bar and on which the control lever runners ride respectively to maintain the clutches released during required periods.

References Cited in the file of this patent UNITED STATES PATENTS 2,059,667 Waechtler et al Nov. 3, 1936 2,273,301 Tuchscherer et al Feb. 17, 1942 2,637,183 Bitzer et a1. May 5, 1953 2,688,861 Fegley Sept. 14, 1954 FOREIGN PATENTS 508,565 Great Britain June 30, 1939 

